12 research outputs found
An Interdisciplinary Approach to Community-Engaged Research Surrounding Lead in Drinking Water in the Mississippi Delta
Childhood lead poisoning is a problem requiring interdisciplinary attention from toxicology, public health, social sciences, environmental law, and policy. In the U.S., Mississippi was ranked as one of the worst states for lead poisoning with limited childhood screening measures. We conducted community-engaged research by working with leaders in the largely rural Mississippi Delta region from 2016-2019 to collect household water samples and questionnaires and involve their communities in lead poisoning risk awareness and outreach. Drinking water from 213 homes was collected and analyzed for pH and lead concentrations. Highest lead concentrations were from households served by private wells, and detectable concentrations at or above 0.09 ppb were found in 66.2 percent of all samples. Nine samples exceeded 5 ppb, and these households received certified sink filters. Findings indicated that community-engaged research and outreach could be used to address data gaps relating to lead in drinking water in rural decentralized water systems
Model of pediatric pituitary hormone deficiency separates the endocrine and neural functions of the LHX3 transcription factor in vivo
The etiology of most pediatric hormone deficiency diseases is poorly understood. Children with combined pituitary hormone deficiency (CPHD) have insufficient levels of multiple anterior pituitary hormones causing short stature, metabolic disease, pubertal failure, and often have associated nervous system symptoms. Mutations in developmental regulatory genes required for the specification of the hormone-secreting cell types of the pituitary gland underlie severe forms of CPHD. To better understand these diseases, we have created a unique mouse model of CPHD with a targeted knockin mutation (Lhx3 W227ter), which is a model for the human LHX3 W224ter disease. The LHX3 gene encodes a LIM-homeodomain transcription factor, which has essential roles in pituitary and nervous system development in mammals. The introduced premature termination codon results in deletion of the carboxyl terminal region of the LHX3 protein, which is critical for pituitary gene activation. Mice that lack all LHX3 function do not survive beyond birth. By contrast, the homozygous Lhx3 W227ter mice survive, but display marked dwarfism, thyroid disease, and female infertility. Importantly, the Lhx3 W227ter mice have no apparent nervous system deficits. The Lhx3 W227ter mouse model provides a unique array of hormone deficits and facilitates experimental approaches that are not feasible with human patients. These experiments demonstrate that the carboxyl terminus of the LHX3 transcription factor is not required for viability. More broadly, this study reveals that the in vivo actions of a transcription factor in different tissues are molecularly separable
Multi-Component Fe–Ni Hydroxide Nanocatalyst for Oxygen Evolution and Methanol Oxidation Reactions under Alkaline Conditions
Iron-incorporated nickel-based materials show promise as catalysts for the oxygen evolution reaction (OER) half-reaction of water electrolysis. Nickel has also exhibited high catalytic activity for methanol oxidation, particularly when in the form of a bimetallic catalyst. In this work, bimetallic iron–nickel nanoparticles were synthesized using a multistep procedure in water under ambient conditions. When compared to monometallic iron and nickel nanoparticles, Fe–Ni nanoparticles show enhanced catalytic activity for both OER and methanol oxidation under alkaline conditions. At 1 mA/cm2, the overpotential for monometallic iron and nickel nanoparticles was 421 and 476 mV, respectively, while the bimetallic Fe–Ni nanoparticles had a greatly reduced overpotential of 256 mV. At 10 mA/cm2, bimetallic Fe–Ni nanoparticles had an overpotential of 311 mV. Spectroscopy characterization suggests that the primary phase of nickel in Fe–Ni nanoparticles is the more disordered alpha phase of nickel hydroxide
Separation of cannabinoid receptor affinity and efficacy in delta-8-tetrahydrocannabinol side-chain analogues
1. The activities of a number of side-chain analogues of delta-8-tetrahydrocannabinol (Δ(8)-THC) in rat cerebellar membrane preparations were tested. 2. The affinities of each compound for the CB(1) receptor were compared by their respective abilities to displace [(3)H]-SR141716A and their efficacies compared by stimulation of [(35)S]-GTPγS binding. 3. It was found that the affinities varied from 0.19±0.03 nM for 3-norpentyl-3-[6′-cyano,1′,1′-dimethyl]hexyl-Δ(8)-THC to 395±66.3 nM for 5′-[N-(4-chlorophenyl)]-1′,1′-dimethyl-carboxamido-Δ(8)-THC. 4. The efficacies of these compounds varied greatly, ranging from the very low efficacy exhibited to acetylenic compounds such as 1′-heptyn-Δ(8)-THC and 4′-octyn-Δ(8)-THC to higher efficacy compounds such as 5′-(4-cyanophenoxy)-1′,1′-dimethyl-Δ(8)-THC and 5′-[N-(4-aminosulphonylphenyl)]-1′,1′ dimethyl-carboxamido Δ(8)-THC. All agonist activities were antagonized by the CB(1)-selective antagonist SR141716A. 5. It was found that a ligand's CB(1) affinity and efficacy are differentially altered by modifications in the side-chain. Decreasing the flexibility of the side-chain reduced efficacy but largely did not alter affinity. Additionally, the positioning of electrostatic moieties, such as cyano groups, within the side-chain also has contrasting effects on these two properties. 6. In summary, this report details the characterization of a number of novel Δ(8)-THC analogues in rat cerebellar membranes. It provides the first detailed pharmacological analysis of how the inclusion of electrostatic moieties in the side-chain and also how alteration of the side-chain's flexibility may differentially affect a CB(1) cannabinoid receptor ligand's affinity and efficacy
Frontiers in Planetary Rings ScienceA Science White Paper for the Planetary Science and Astrobiology Decadal Survey 2023-2032
A Science White Paper for the Planetary Science and Astrobiology Decadal Survey 2023-203